This invention relates to a vacuum-type circuit interrupter and, more particularly, relates to guide means for the movable contact rod of such an interrupter.
The usual vacuum interrupter comprises an evacuated envelope including an end plate having a central opening, a contact rod extending through the central opening, and a tubular bellows surrounding the contact rod and having its inner end joined to the contact rod and its outer end joined to the end plate. For guiding the contact rod, it is customary to provide a tubular guide which is supported on the end plate and extends into the tubular bellows, as is illustrated, for example, in U.S. Pat. No. 4,071,727--Crouch et al.
While this type of guide is quite effective, it is subject to a number of disadvantages. One is that the tubular bellows must have a relatively large internal diameter in order to accommodate the tubular guide which is located therein. Another is that the guide is relatively expensive when it is considered that it must be suitably attached to the end plate in a precise position in order to perform its desired function.